Keychron B39 Wireless Keyboard vs Keychron B4 Pro Ultra Slim Wireless Keyboard
Keychron B4 Pro Ultra Slim Wireless Keyboard — Pick the Keychron B4 Pro Ultra Slim Wireless Keyboard — it leads these groups: Design 1 Connect 1
Tap a group name to see the proof · The scoring method is public
The short answer
Keychron B4 Pro Ultra Slim Wireless Keyboard wins this comparison with a score of 57.0/100, ahead of Keychron B39 Wireless Keyboard (56.8).
The main differences: Key count (84 vs 100) · Wired (— vs ✓).
Scores are computed from 5 public spec attributes; missing values stay marked unknown in tables and are imputed at the category median, never passed off as measured.
At a glance
0–100 per group, normalized within the category · Tap a group for details
How to choose
Pick the Keychron B4 Pro Ultra Slim Wireless Keyboard if you care about…
- Key count 100 +16 vs 84
- Wired ✓ vs —
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Where they differ
2 · Only rows that actually differ, with a verdict per row
| Keychron B39 Wireless Keyboard | Keychron B4 Pro Ultra Slim Wireless Keyboard | Where they differ | |
|---|---|---|---|
| Key count | 84 | 100 | Keychron B4 Pro Ultra Slim Wireless Keyboard |
| Wired | — | ✓ | Keychron B4 Pro Ultra Slim Wireless Keyboard |
The record
Grouped and collapsible · Tap a group to fold
Design3▾
| Keychron B39 Wireless Keyboard | Keychron B4 Pro Ultra Slim Wireless Keyboard | |
|---|---|---|
| Layout | QWERTY | QWERTY |
| Hot-swappable | — | — |
| Key count | 84 | 100 |
Connect1▾
| Keychron B39 Wireless Keyboard | Keychron B4 Pro Ultra Slim Wireless Keyboard | |
|---|---|---|
| Wired | — | ✓ |
Feel1▾
| Keychron B39 Wireless Keyboard | Keychron B4 Pro Ultra Slim Wireless Keyboard | |
|---|---|---|
| Switch type | Scissor-switch | — |
Data sources: Amazon
FAQ
Which is better, Keychron B39 Wireless Keyboard or Keychron B4 Pro Ultra Slim Wireless Keyboard?
Keychron B4 Pro Ultra Slim Wireless Keyboard edges ahead 57 to 57 and leads in Design, Connect.
What are the main differences?
The main differences: Key count (84 vs 100) · Wired (— vs ✓).
How are the scores calculated?
We normalize 5 public spec attributes within the category and weight them by group into a 0–100 score; missing values are inherited from spec-identical twins or imputed at the category median, so a sparse spec sheet never earns an advantage. The methodology is public.